Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China

Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year （2003）, the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.

Analysis of the Influence Factors of Grain Supply-Demand Gap in China

Based on the analysis of the grain supply and demand gap’s current situation in China, this paper establishes an indicator system for the influence factors of grain supply and demand gap. Then this paper calculates the correlation degree between the main grain varieties’ supply and demand gap and its influence factors. The results show that sown area and unit yield have the greatest impact on wheat supply and demand gap;per capita disposable income and unit yield have the greatest impact on corn supply and demand gap;per capita disposable income and agricultural mechanization level have the greatest impact on the supply and demand gap of soybean and rice. From the analysis results, we can obtain the difference between the factors affecting the grain supply and demand gap, and provide a certain theoretical basis and new ideas for the balance of grain supply and demand in China.

Analysis of China’s Crude Oil Supply and Demand in the Year 2010 and the Year 2020

Along with the speedy development of the economic growth in China, the shortage of oil and gas becomes more and more serious. Based on summarizing some related research results, the prediction of China＇s oil demand and supply in the year 2010 and the year 2020 has been given in the paper. The oil supply and demand situation is discussed on three different levels. Accordingly, suggestions about the oil supply safety and the national economy safety strategies have been given.

THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR

The Hexi Corridor is an important base of agriculture development in Northwest China. According to recent statistics, there are 65.94×108m3 of water resources available in the Hexi Corridor. At present, net consumption in development and utilization is 43.33×108m3. Water supply and demand reach a balance on the recent level of production, but loss of evaporation and evapotranspiration is as much as 25.69×108m3. So net use efficiency of water resources is 59%. Based on analyzing balance between water and land considering ecological environment at present, there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded. There is a comparative balance between supply and demand of water resource in the Heihe River system; and the Sule River system has some surplus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass for 6.9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water saving efficiency of irrigation is about 10% by using such traditional technologies as furrow and border dike irrigation and small check irrigation, and water saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. can save more than 60% of irrigated water. Incremental irrigation area for water saving potential in the Hexi Corridor has been estimated as 56%-197% to original irrigation area. So the second water sources can be developed from water saving agriculture in the Hexi Corridor under Development of the Western Part of China in large scale. This potential can be realized step by step through developing the water saving measures, improving the ecological condition of oasis agriculture, and optimizing allocation of water resources in three river systems.

The Supply and Demand of Agricultural Products in China Based on Balanced Diet

Promoting agricultural production and ensuring the supply of agricultural products has always been the main task of agricultural development in China,but the agricultural production in China has not yet been combined with the Chinese residents' dietary needs to formulate reasonable development goals,with a certain blindness in production. According to the dietary standards in The Dietary Guidelines for Chinese Residents developed by the Chinese Nutrition Society,we calculate the demand of various types of agricultural products in China under the conditions of balanced diet. In comparison with the output of various types of agricultural products in China at present,we find that the output of most of agricultural products in China has exceeded the reasonable demand of the Chinese residents under the conditions of balanced diet. Therefore,adjusting the agricultural production structure in China and advocating balanced diet has become an important way to solve the problem of balance between supply and demand of agricultural products.

The Supply-Demand Analysis and Mechanism Innovation of Chinese Rural Public Goods

The connotation of rural public goods is expounded.The rural public goods refer to the products and labors that satisfy the production and living of rural residents,economic growth and social progress.The rural public goods is characterized by non-excludability,non-competitiveness and indispensability of other general public goods.The supply situation of Chinese government to rural public goods is analyzed,as well as the demand situation of rural public goods,which includes farmers' demand on training,the assistance demand of rural weak groups,farmers' demand on comfortable living conditions and farmers' demand on "soft" public goods.The paths for innovating the supply mechanism of rural public goods are put forward,which cover perfecting the decision mechanism of public goods supply;scientifically distributing the supply responsibility of rural public goods;facilitating the reform of each supporting equipment and exploring the multiple capital collecting channels of rural public goods.

Characteristic analysis and forecast of electricity supply and demand in APEC

The Asia Pacific Economic Cooperation(APEC)comprises of the world’s largest producers and consumers of energy,accounting for 60.3%of primary energy supply,50.0%of final energy consumption,and 63.0%of electricity generation worldwide in 2016.This study discusses the primary energy supply and final energy consumption situation of the APEC and analyzes the characteristics of electricity in terms of its generation structure based on fuel,consumption by the end-use sector,access to electricity,and so on.The renewable energy and electricity generation projections up to 2030 based on trends in the APEC are also assessed.It is seen that electricity in final energy consumption has been on an upward trend,with an average annual growth rate of about 4.8%during 2006–2016,in 2016,its share reached 24.3%.The industry sector consumes the largest share of electricity,accounting for about 45.5%in 2016.Coal supply and consumption peaked in 2011 and then began to decline,while renewable energy has been on an upward trend,with its primary energy supply share increasing from 4.80%in 2010 to 6.29%in 2016.Solar photovoltaic and onshore wind power are on the verge of costing less than the operating cost of existing coal-fired plants in 2018.In the APEC’s target scenario in which renewable energy is doubled,the predicted net growth from 2017 to 2030 of solar,wind,and hydro power is about 963,497,and 157 GW,respectively,and to reach this target,the APEC economies need to accelerate renewable energy development.

Analysis on the Situation of Power Supply and Demand in Shandong

In the first half of 2007, the power industry in Shandongprovince continued to maintain a rapid growth momentum.The gross electricity consumption amounted to 121.25 TWh,14.4% higher over that in the same period of last year. The totalinstalled capacity reached 53.29 GW. It was expected that bythe end of 2007, the gross electricity consumption in Shan-dong would reach 260 TWh, increasing by 14.4% on ayear-on-year basis; the maximum load would reach 40.

Development and Utilization of the World＇s and China＇s Bulk Mineral Resources and their Supply and Demand Situation in the Next Twenty Years

Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world＇s and China＇s economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world＇s and China＇s supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources （especially iron ores and copper ores） are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserve- production ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world＇s six mineral products will exceed the demand in the future twenty years. In 2015-2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4-0.7 billion tons （Gt）, 5.0-6.0 million tons （Mt）, 1.1-8.9 Mt, 1.0-2.0 Mt, 1.2-2.0 Mt and 4.8-5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China＇s compressed industrialized development model, the demand of iron ores （crude steel）, potassium salt, refined lead, refined copper, bauxite （primary aluminum） and zinc will gradually reach their peak in advance. The demand peak of iron ores （crude steel） will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite （primary aluminum）, 2022 for refined copper and 2023 for zinc. China＇s demand for iron ores （crude steel）, bauxite （primary aluminum） and zinc in the future 20 years will decline among the world＇s demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015-2035, China＇s accumulative demand for iron ores （crude steel） will be 20.313 Gt （13.429 Gt）, 0.304 Gt for refined copper, 2.466 Gt （0.616 Gt） of bauxite （primary aluminum）, 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world＇s YOY （YOY） accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China＇s bulk mineral resources, it is forecasted that the accumulative supply of primary （mine） mineral products in 2015-2035 is 4.046 Gt of iron ores, 0.591 Gt of copper, 1.129 Gt of bauxite, 63.661 Mt of （mine） lead, 0.109 Gt of （mine） zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world＇s predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000-2014, the rate of capacity utilization for China＇s crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015-2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015-2035 the accumulative utilization amount of steel scrap （iron ores） is 3.27 Gt （5.08 Gt）, 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China＇s bulk mineral resources in 2015-2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China＇s iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%, -0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly. （1） The demand peak of China＇s crude steel and potassium salt will reach during 2015-2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak. （2） The supply-demand contradiction of China＇s bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities. （3） China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of ＂reducing excess production capacity＂. （4） In accordance with the national strategic deployment of ＂One Belt One Road＂, China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly. （5） It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling. （6） China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources.

Oil and Gas Supply and Demand in China and Its Development Strategy

The paper makes a comprehensive prediction of China＇s future demand for oil and gas with two methods, i.e. the prediction method based on the demand for individual oil and gas products and the method for predicting the total demand. According to the demand prediction of, and the historical data on, the oil and gas consumption, we conduct an analysis of the oil and gas consumption trends, which can be described as six different development periods. On the other hand, the paper makes a comprehensive analysis of the domestic oil and gas resources and, on this basis, makes a basic prediction of the domestic output of oil and gas. The supply and demand situation is also analyzed. By using the SWOT analysis method, the paper puts forward the development strategies for China＇s oil and gas industry and gives some related strategic measures.

Risk Analysis and Solution Recommendations on Uranium Supply forNuclear Power in China

The Chinese government has set ambitious goals for the development of nuclear power, which is under the risks from uranium supply shortage. The supply and demand of uranium resources both domestically and abroad is firstly analyzed in the paper. The supply can still meet the demand in the short run, but the risk of shortage may exist in the long run. Moreover, the lack of uranium resources will exist globally no matter at present or in the future. Therefore, the main factor restraining the nuclear power development in China is the short supply of uranium. Finally, recommendations are put forward such as strengthening the exploration and production of domestic uranium, cooperating with foreign enterprises in the exploration of uranium mines, building the reserves, and proactively developing the fourth generation of nuclear power technology and so on.

Supply Chain Demand Forecast Based on SSA-XGBoost Model

Supply chain management usually faces problems such as high empty rate of transportation, unreasonable inventory management, and large material consumption caused by inaccurate market demand forecasts. To solve these problems, using artificial intelligence and big data technology to achieve market demand forecasting and intelligent decision-making is becoming a strategic technology trend of supply chain management in the future. Firstly, this paper makes a visual analysis of the historical data of the Stock Keeping Unit (SKU);Then, the characteristic factors affecting the future demand are constructed from the storage level, product level, historical usage of SKU, etc;Finally, a supply chain demand forecasting algorithm based on SSA-XGBoost model has proposed around three aspects of feature engineering, parameter optimization and model integration, and is compared with other machine learning models. The experiment shows that the forecasting result of SSA-XGBoost forecasting model is highly consistent with the actual value, so it is of practical significance to adopt this forecasting model to solve the supply chain demand forecasting problem.

Tilt Angle Optimality Criteria for Stand Alone PV Systems

The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy availability varies, this criterion may not be optimal. This study explores two alternative optimization criteria focused on maximizing baseload supply potential and minimizing required storage capacity to address seasonality in energy generation. The optimal tilt angles determined for these criteria differed significantly from the standard approach. This research highlights additional factors crucial for designing solar power systems beyond gross energy generation, essential for the global transition towards a fully renewable energy-based electric grid in the future.

Land Use Allocation Based on Interval Multi-objective Linear Programming Model: A Case Study of Pi County in Sichuan Province

Adjusting and optimizing land use structure is one of the essential approaches to solve the conflict between land supply and demand. In this study,an uncertain interval multi-objective linear programming model was established and applied to analyzing the suitability of land use structure in Pi County of Sichuan Province. An adjustment scheme for optimizing land use structure was proposed on the basis of development planning drawn up by the local government. The results are summarized as follows: 1) the optimal adjustment scope for cropland area ranges from 27 976.75 ha to 31 029.08 ha,and the current area is less than the lower limit of the scope; 2) the optimal adjustment scope for garden land area ranges from 4 736.49 ha to 12 967.11 ha,and the current area is less than the lower limit; 3) the optimal adjustment scope for construction land ranges from 7 761.95 ha to 10 393.18 ha,and the current area is greater than the upper limit; 4) the optimal adjustment scope for industry and mining land ranges from 557.29 ha to 693.54 ha,and the current area exceeds the upper limit; and 5) the areas of forest land,grassland and other agricultural land are within the optimal adjustment scope. In order to maximize comprehensive benefit with the limited resources and the demand of sustainable development,the areas of cropland and garden land are supposed to be expanded properly,while the construction land should be controlled and reduced gradually,and the forest land and other agricultural land can be maintained at the current level in short period.

Technical System Construction in the Market Trading System for Demand Response Based on the Energy Internet

With the explosive growth of variable renewable energy,the balance between the supply and demand of the power grid is faced with new challenges.Based on the development experience from typical countries and the state quo in China,this paper further analyzes the system architecture and development trend of demand response under the background of Energy Internet.Five dimensions are considered:Energy Internet platform,demand response application scenarios,system architecture,information technology system construction,and demand response development trend.The results show that the application of the Energy Internet platform can effectively solve the problems of data acquisition and processing,“terminal-edge-network-cloud”cooperation of demand response,etc.The system architecture of the demand response platform that supports user resource management,user information access,control instruction receiving,control strategy issuing,and response process monitoring is proposed in this paper.It is also helpful to provide a feasible technical choice for expanding the application services of Energy Internet towards government and society.

中药饮片产业发展现状及供给侧问题与对策

分析了中药饮片产业及市场规模现状,相关法律、法规、政策等,从供给侧剖析产业发展瓶颈,解析中药饮片生产标准化、规模化程度低,技术及产品创新不足,缺少协调供需平衡的宏观统筹问题,提出加强炮制理论基础研究、提高中药饮片生产标准化水平的对策措施,包括提高中药炮制技术的标准化水平、完善质量控制标准、建立等级标准等,倡导提高产业规模化水平、实施大品种战略、鼓励科技创新、组建创新联合体,加快中药饮片数字化、智能化生产管理研发及新产品研发,并从调控供需平衡角度提出了推进中药饮片区域化生产与流通的措施等,以期构建以高品质中药饮片为核心的创新型产业发展格局,探寻振兴中药饮片产业高质量发展之路。

基于生态需水的黄河中游水平衡分析--以沁河流域为例

为推动黄河流域生态保护及高质量发展,解决地表水资源供需矛盾,亟需开展水平衡分析,建立水平衡模型,为水资源合理分配提供参考依据。作为黄河的重要支流,沁河流域位于黄河中游末端,由于近年来上游调水政策的施行以及流域内生活、生产用水的增加,用水矛盾突出,出现了河道断流、入黄水量偏枯等问题。为保障河流生态环境健康,优化引沁入汾跨流域提水工程实施后的流域水资源供需平衡,以2021年为现状年,在“自然-人工”二元水循环研究理论的指导下,运用水平衡分析理论与方法,以河道内生态需水为保障基础,对沁河流域水资源需求、供水能力与供需平衡进行了分析与讨论。结果表明:(1)沁河流域水资源供给和需求在空间分布上具有分异性,上游山西省境内各河段河道内均能够保障适宜的生态需水量,下游河南省境内,仅可满足最小生态需水量;(2)沁河流域可供给水资源总量为10.04×10^(8)m^(3),河道外生产、生活及生态用水总量为8.89×10^(8)m^(3),剩余河道内水量仅为1.15×10^(8)m^(3),仅可满足河流最小生态需水;(3)推算至2030年,流域内工业生产及生活取用地表水量将达到6.98×10^(8)m^(3),河道外用水总量将达到9.81×10^(8)m^(3),剩余水量无法满足最小生态需水。建议采用降低工业用水量、提高农田灌溉用水利用率、推广使用高效节水技术,进一步增强水资源的有效利用,改善流域生态环境。研究结果可为合理规划沁河流域水资源调度提供参考,也可为黄河中游水平衡分析提供范例。

山地多中心城市公园绿地生态系统文化服务供需匹配特征

城市公园绿地为居民提供了重要的生态系统文化服务,在促进居民身心健康和提高社会福祉方面发挥着关键作用。以典型山地城市重庆中心城区为例,构建供需匹配评估体系,利用多源数据量化供给与需求,识别供需平衡与协调发展关系。结果表明:(1)重庆市中心城区城市公园绿地生态系统文化服务供需具有显著空间异质性,供给呈北高南低、分散布局的格局,需求呈中心高、外围低的格局;(2)生态系统文化服务供需失衡特征显著,其中52.38%的组团文化服务供给滞后,33.33%的组团属于供给超前状态;供需耦合协调指数平均值为0.50,协调发展程度空间分布呈“中心高、外围低”格局;(3)综合分析供需均衡与耦合协调结果发现,由于供给超前导致了外围城市组团的失调发展,而城市中心区域组团在供给滞后状态下维持了中等水平协调发展程度。总体来看,重庆市中心城区各组团存在不同程度的公园绿地生态系统文化服务供需错配,基于评估提出针对性的城市公园绿地优化策略,可为公园绿地的合理配置与规划提供重要支持。

水生态系统韧性视角下热带雨林地区的蓝绿空间评价——以五指山市南圣河为例

热带雨林地区因特殊的气候特点及空间特征,河流蓝绿空间面临的雨洪压力与人类社会活动压力较大,其韧性建设对于整个生境具有关键性影响。国内外研究聚焦于韧性承洪实践与韧性评估量化,鲜有基于不同生态压力冲击对河流蓝绿空间开展多维韧性评价。文章以南圣河为对象,基于雨洪等自然灾害的脉冲式压力与人类社会对生态系统施加的慢性压力两类情境,构建水生态系统的“压力-脉冲-韧性”模型,通过“构建理论模型―叠合双维承压评价―解析吻合/冲突点―探析韧性策略”的逻辑方法实现特定地域蓝绿空间的评价与优化。研究发现:1)生态系统服务价值越高,调节功能越高,蓝绿空间韧性越强。2)突发性脉冲方面,在极端日降雨量增加情景下,河流水系的缓冲半径与水源类型密切相关,水库受到水安全威胁的风险大于河流,地表的径流曲线数值(简称CN)一般与历史经验相关。3)慢发性压力方面,韧性压力与城市人口密切相关,人口越密集,韧性压力越大;且不同季候的游憩密度与丰枯期存在分异,丰水期雨洪威胁大,游憩密度低,枯水期雨洪威胁小,游憩密度高。

2024年我国无烟煤市场发展与展望

通过对宏观政策以及产业政策动态等多维度进行剖析,对无烟煤下游行业的消费现状和趋势进行详细分析和预测。介绍了我国无烟煤资源分布、生产和进口现状,对我国无烟煤生产和进口趋势进行了预测。综合分析供需、成本、政策等影响无烟煤价格的因素,特别是需求和供应关系,对2024年无烟煤价格走势进行了定性分析。整体认为,2024年,我国无烟煤将处于供需紧平衡状态,但较2023年略有宽松;价格中枢有望小幅下移,但仍将处于相对较高的位置。